Modular hood for mechanized sweeper

ABSTRACT

A hood for a mechanized sweeper has dual portions connected via a mating surface and includes several downward depending flaps for increasing volumetric efficiency of defined vacuum plenum. The three flaps consist of a front flap, a middle flap, and a rear flap, and are of a cartridge type to facilitate replacement. The front and rear flaps are adjustable to allow for lowering of these two flaps in the event of wear due to friction against a paved road surface. A mechanism for raising the leading edge of the hood is also provided.

FIELD OF THE INVENTION

The present invention relates to mechanized sweepers. Particularly, sweepers used for sweeping paved areas, roads, paved motor vehicle parking lots, parking areas, parking structures and debris covered surfaces. More particularly, the invention relates to the hood of the mechanized sweeper.

BACKGROUND OF THE INVENTION

Various types of sweepers are used in sweeping paved surfaces. For example, truck mounted sweepers sweep highway and roadway surfaces. In general, pavement sweepers include a standard truck or specially designed chassis upon which the sweeper unit is mounted. Three basic categories of sweeper units are: re-circulating air sweeper, mechanical sweeper, and vacuum air sweepers. Generally, re-circulating air sweeper units include a motor driven fan, sweeping hood, a curved brush, and a debris separation hopper. The curb brush brings the debris into the path of the sweeping hood. The fan re-circulates airflow from the hopper through the sweeping hood and back into the hopper where dust, particles, and other debris are removed from the airflow by known separation techniques.

In re-circulating air sweepers, the sweeping hood is prone to maintenance from wear and damage. For example, the sweeping hood extends outside the wheel base and may hit objects that the truck otherwise avoids. Particularly, when the truck is cleaning parking lots and parking structures, it is also more likely the hood may hit curbs and support structures within the parking area. Exacerbating this problem, because debris may tend to clump in corners, drivers are forced to drive deep into the corners and near the curbs and support structures which further increases the likelihood of damage from hitting objects. In order to fix the damaged hood, the entire hood must be removed from under the sweeper in a labor and time intensive procedure.

In addition to damage, the hoods are subject to wear. The hoods include a series of rubber flaps that allow for debris to pass under the hood and be trapped until the re-circulating air may lift the debris into the hopper. The flaps extend to the ground so that the debris may be directed toward the hopper by the re-circulating air. As the sweeper moves through the parking lot, the flaps wear against the pavement. As the flaps wear against the ground, the flaps lose material. Once the material is lost from the flaps, then the hood is no longer able to contact the paved surface at the same hood height. If the flaps do not contact the surface, then the air that is re-circulated under the hood is no longer directed toward the hopper. Instead, the re-circulated air may flow out from underneath the hood and push debris out from the hood back onto the pavement.

In order to alleviate these problems, the driver generally employs one of two methods. The driver may lower the entire hood, or the driver may replace the rubber flaps. Replacing the rubber flaps requires removing the entire hood from under the sweeper and setting the flaps into the sweeper hood. By replacing the flaps, the hood height is maintained according to the original configuration. Alternatively, the driver may lower the hood so that the rubber flaps again contact the paved surface. Lowering the hood changes the dynamics of the hood. As the hood is lowered, the path of the re-circulating air changes in cross-sectional size. The decreased cross-sectional size requires higher air velocity to maintain the same flow rates. Higher flow rates changes the size of the debris that may be removed, such that larger debris will no longer be picked up by the re-circulating air flow. Therefore, the driver must decide between incomplete sweeping from a lowered hood or increased downtime from constantly replacing flaps.

Eventually, the flaps must be replaced when the flaps are worn down too low. Replacing the flaps requires removing the entire hood from the sweeper. In a one piece embodiment, the sweeper may need to be elevated prior to removal, and the hood is large and unwieldy to handle. In addition, if a portion of the hood has been damaged, it is likely that the rubber flaps may not be easily replaced without replacing the entire hood.

SUMMARY OF THE INVENTION

An aspect of the invention provides a hood for a mechanized sweeper. The hood comprises a left portion, a right portion, a central mating surface, and connectors. The left portion has an upper surface extending in a first direction. The right portion has an upper surface extending in the first direction. The central mating surface is configured to attach to the left portion and the right portion. The connectors are configured to attach the left portion and the right portion to the central mating surface.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram of a re-circulating air sweeper;

FIG. 2 is a view of the hood of the sweeper of FIG. 1;

FIG. 3 is another view of the hood of the sweeper of FIG. 1;

FIG. 4 is an expanded view of the hood of FIG. 1;

FIG. 5 is a view of a front flap of the hood of FIG. 1;

FIG. 6 is a view of a cartridge flap of the hood of FIG. 1; and

FIG. 7 is a view of the hood including connections to the sweeper.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Turning now to the drawing figures, FIG. 1 is a diagram of a re-circulating air sweeper 10. The sweeper 10 includes a cab 12, a fan 14, a motor 16, a sweeping hood 18, a curb brush 20 and a hopper 22. The sweeper 10 is generally a specialized vehicle supported on four tires 26 and mounted on a standard utility truck chassis. As the sweeper 10 moves down a road, debris and trash under the hood 18 pass through a flexible hose 28 to the hopper 22 for collection. The brushes 20 in front of the hood 18 rotate and push debris into the path of the hood 18. The fan 14 blows air through one side of the hood 18. The air is then returned to the hopper 12 through the flexible connecting member 28. In this embodiment, the fan is located on the passenger's side and the return is located on the driver's side of the vehicle 10. Having the return 28 on the driver's side allows for a driver to better align the portion of the hood 18 under the return 28 with trash and debris that is moving under the driver and along the curbs. However, reversing the position of the fan and the return such that the fan 14 is on the driver's side and the return 28 is on the passenger's side may also effectively remove debris and trash from the surface.

The fan 14 is powered by the motor 16. An intake 21 of the fan 14 pulls air from the hopper 22, pushes the air through a hood entry and passes the air through the hood 18 back through the return 28 into the hopper 22. Within the hopper 22, a filter filters the air prior to passing the air through the intake 21. In this manner, the air that enters the fan 14 is filtered from small debris which may have been picked up through the air if the intake was vented to atmosphere. The motor 16 is configured to power the re-circulating air sweeper system, but is not responsible for propulsion of the sweeper 10. However, fluid reservoirs meant to supply both the motor 16 and the engine of the sweeper 10 may be shared between these two components.

Turning now to FIG. 2, FIG. 2 is a view of the hood 18 of the sweeper 10 of FIG. 1. The hood 18 includes a left section 30, a right section 32, a central mating section 34, and a front flap 36. The left and right sections 30 and 32 are generally similar in shape and size and are mirror images of one another along a central axis across the central mating section 34. Generally, the left and right sections 30 and 32 include a rectangular elongated top surface 40 and a skirt end 42. The skirt end 42 is oriented perpendicular to the elongated top surface 40 extending downward from the top surface 40 and extending parallel to the short axis of the elongated top surface 40. The left and right sections 30 and 32 also include sweeper connections 46 for connecting the hood 18 to the sweeper.

Opposite the skirt end 42 on left section 30, at top surface 40 along its long axis, mating structures 50 are configured to connect sections 30 and 32 via central mating section 34. Therefore, as may be seen, central mating section 34 attaches the left and right sections 30 and 32 to each other. The central mating section 34 also allows for each side section 30 and 32 to be removed individually from the hood 18 as opposed to a single piece type hood where the entire hood would need to be removed to repair any damage to the hood.

The central mating section 34 is configured to overlay portions of the side sections 30 and 32 and are connected so that the hood 18 is structurally stiff. However, the connectors 50 between the central mating section 34 and the side sections 30 and 32 may be configured to shear forces exerted on the side sections 30 and 32 such that damage does not occur to side sections 30 and 32, but instead cause damage to a simple connector. The sections, then, are relatively resilient to direct impacts while maintaining stiffness during normal operating conditions.

If a side section 30 or 32 is damaged, then repair may be achieved quicker and more cost effectively by having to only replace a single side portion 30 or 32. Access to a single side portion 30 or 32 is less labor intensive than fully removing the entire hood. In addition, replacing only a single side section 30 or 32 does not require removing additional connections between the hood 18 and the sweeper. Moreover, the lower costs associated with shipping smaller parts at less weight also reduce the total cost of maintenance.

As more clearly shown in FIGS. 3 and 4, front flap 36 of hood 18 extends from underneath raised sections 31,33 of left and right portions 30 and 32, respectively, and arcuately falls forward and downward to contact a pavement underneath hood 18. Flap 36 is bounded on each side by end skirts 42 and 42′ and is affixed to the underside of raised portions 31,33 via fasteners 73. A supporting bracket rod 74 also biases flap 36 against the underside of portions 31,33 when the two connectors 60 are tightened. As shown, a slot is formed through portions 31,33 through which connectors 60 intersect rod 74. Flap 36 also includes corresponding slots 80 through which connectors 60 pass to engage rod 74. A middle flap 76 is positioned rearward from front flap 36 but in proximity thereto, and is affixed to the underside of portions 30,32 near portions 31,33.

As shown in the figures, flap 36 is held in stationary position by bracket rod 74 relative to middle flap 76, which is fixed. Fasteners 60 may be loosened and moved rearward within the slot 35 formed in portions 31,33 to allow flap 36 to fall vertically under its own weight, thereby lengthening flap 36. Since flap 76 is raised slightly relative to flap 36, debris flows relatively easily under hood 18 from the front. Rear flap 64 is longer relative to middle flap 76, but typically of equal vertical height with flap 36. Flaps 64, 76 and 36, in conjunction with end skirts 42 and 42′ form a vacuum plenum into which debris on the pavement are swept through forward motion of sweeper 10 and brooms 20. “Vacuum plenum” is hereby defined as the volume of space defined under the hood 18 into which road debris is swept and within which air is held a pressure less than ambient atmospheric pressure during operation of said sweeper 10.

The vacuum plenum is ideally a constant volume chamber. When the end skirts 42, and 42′ abut the ground, the volume of the plenum is approximately the product of the length and width of the elongated top surfaces 40 and the height of the end skirts 42. A constant volume chamber allows for a continuous airflow through the plenum at a known negative pressure. As air enters the plenum from the fan 14, an equal amount of air exits the plenum through the flexible hose 28. At each cross section parallel to the end skirt 42 through the plenum, an equal amount of air travels. If the cross section parallel to the end skirt 42 is reduced in size, an increased velocity of air must flow through the plenum in order to move the same volume of air entering and discharging through fan 14. In accordance with Bernoulli's principle, as air moves faster, the pressure drops across a surface. A drop in pressure, therefore, determines the size and weight of the debris removed from a road paved surface as the sweeper 10 traverses over a paved road surface.

Based on these principles, front flap 36 and the end skirts 42 must abut the paved road surface so that air does not flow out from under the hood 18. The front flap 36 and the end skirts 42 direct flow of air from the fan to the flexible hose 28 and if the front flap does not reach the pavement, air will escape under the hood 18 over the paved surface. Escaping air may even push debris away from the hood 18 further limiting the ability of the air to bring debris under the hood 18 and into flexible hose 28.

The front flap 36 is flexible such that debris hitting the flap deform its leading edge rearward so that the debris may enter the plenum for collection. However, due to road surface irregularities, front flap 36 contacts the pavement and losses material due to wear. Over time the flap does not fully contact the pavement and the volumetric efficiency of the hood 18 is reduced. To counteract this wear, front flap 36 is configured so that the flap may be lowered relative to the hood 18. Connectors 60 attach the front flap 36 to the hood 18 and are received through a slot 35 and a corresponding slot 80 (see also FIG. 5) in the front flap 36 and are threaded through the hood 18. As connectors 60 are tightened, front flap 36 is compressed and locked in place with bracketed rod 74 between the connector 60 and the hood 18. The compressed front flap 36 then does not move relative to the hood 18, but when connectors 60 are loosened front flap 36 may be moved rearward relative to the hood 18 along slots 35 formed therein. This action restores or improves contact with the pavement. Thus, instead of replacing an entire front flap 36, or being forced to lower hood 18, the length of the front flap 36 may be adjusted to maintain space under the hood 18 and maintain the contact with the pavement. Vacuum efficiency is thereby economically maintained.

The hood 18 also includes a rear cartridge flap 64 which extends vertically downward from the upper surface 40 and abuts the pavement at the rear part of the hood 18. Cartridge flap 64 is supported by hood 18 via rear connectors 70. Rear connectors 70 are threaded into the cartridge flap 64 and the hood 18 such that as rear connectors 70 are rotated, the rear cartridge flap 64 may be lowered toward the ground.

The cartridge flap 64 includes a rigid member 86 to attach it to rear connectors 70. The rigid member 86 is formed from an upper U-shaped member and a downward projecting straight support member. The upper U-shaped member is inverted such that the horizontal part of the U-shaped member may receive the rear connectors 70, and is rigidly fixed to the underside of the hood 18. A straight resilient member 88 extends downward a short distance from member 86 to contact the pavement and is flexible. While flap 36 tends to flexibly deform to allow pavement debris to enter underneath hood 18, rear flap 64 is stiffer to avoid debris rolling out rearward from underneath hood 18.

In a fashion similar to front flap 36, the purpose of the rear cartridge flap 64 is to maintain the depth of the hood 18 and maintain contact between the hood 18 and the pavement. As the rear cartridge flap 64 is worn away from contact with the pavement, the rear connectors 70 may be advanced so that the bottom edge of the rear cartridge flap 64 may maintain contact with the pavement without having to drop the hood 18 downward. Slots 87 are formed in member 86 to allow the fixing of flap 64 against a rear trailing portion of hood 18 with fasteners 85, while allowing its lowering thereof.

FIG. 4 is an expanded view of the hood 18 of FIG. 2. The hood 18 includes the left section 30, the right section 32, the central mating section 34, the front flap 36, the rear cartridge flap 64, a support bar 74, and interior middle flap 76. The support bar 74 extends along the long axis of the hood 18 between the end skirts 42,42′ and receives connectors 60 through slots 35 formed in portions 31 and 33. The front flap 36, then, is compressed upon the support bar 74 so that the front flap 36 may be fixed, but includes adjustability through the connectors 60 to allow for lowering of the front flap 36 as discussed above.

The interior middle flap 76 is located behind the front flap 36. The middle flap 76 acts as a volumetric check valve for the plenum. As debris passes the front flap 36, the circulating air under the hood may not escape because the air flows between the interior flap 76 and the rear cartridge flap 64. As the debris passes the front flap 36, the front flap falls back into contact with the pavement and the interior flap 76 maintains close proximity with the pavement and the integrity of the plenum under the hood 18 is thereby maintained.

FIG. 5 is a full view of the front flap 36 of the hood 18 of FIG. 2. The front flap 36 includes slots 80. The slots 80 are configured to receive the connectors 60 through slots 35 of the hood 18 and are configured so that the front flap 36 may be slidably advanced relative to the hood so that the front flap 36 may maintain contact with the paved surface. A lower edge 82 of the front flap 36 is the lower-most projection of the front flap 36 and engages the pavement over which the hood moves, causing wear. The slots 80 in the flap 36 allow for more of the flap 36 to be used prior to removing the flap 36 because the flap 36 may be lowered a distance equal to the length of the slot 80. Thus, edge 82 of the flap 36 may be incrementally worn a distance equal to the length of the slot 80, thereby also reducing any environmental impact of dislodged portions of the front flap 36.

Increasing the total length of the flap 36 also increases the life of the front flap 36. As debris contact the front flap, the additional rubber that is flexed over the upper surface of the hood absorbs some of the impact from the debris. Thus, more of the flap 36 may be used to engage debris and the wear of the flap 36 is reduced.

FIG. 6 is a view of the rear cartridge flap 64 of the hood 18 of FIG. 3. The cartridge flap 64 includes a cartridge portion 86 and a flexible rubber member 88. The cartridge 86 is configured to receive rear connectors 70, and connectors 85 through slot 87, to set the depth of the rear cartridge flap 64 over the pavement. The cartridge 86 also includes the rubber member 88, a flexible but resilient lower portion of rear flap 64.

The use of the cartridge 86 allows for minimal rubber use in the rubber member 88, because cartridge 86 (and thus the rubber member 88) may be lowered to a desired depth via rear connector 70, such that sufficient height is maintained above the pavement while maintaining sufficient volumetric integrity of the plenum over the pavement.

As may be seen, the cartridge 86 is coupled to the rubber member 88 through a plurality of connectors 89 located along the length of the cartridge flap 86 and the rubber member 88. In another embodiment, the cartridge 86 may slidably receive the rubber member 88 laterally, for example through a dove tail joint between the cartridge 86 and the rubber member 88. The rubber member 88, then, would be supported in the hood by the cartridge 86 and held in place laterally by the end skirts of the hood. In another embodiment, the rubber member 88 may be attached to the cartridge 86 by a compression member exerting a force to squeeze the rubber member 88 to the cartridge 86. The compression member is configured to fixedly attach the rubber member 88 to the cartridge 86. Because the rear flap 64 may be more rigid than a front flap, the length of the cartridge may be elongated to increase stiffness. Increased stiffness may come at the expense of more frequent replacement, as the rubber member 88 is likely to wear faster and the amount the flap may be lowered is limited to the depth of the rubber member 88.

Turning now to FIG. 7, FIG. 7 is a view of the hood 18 including connections to the sweeper 10. The hood 18 is configured to attach to the sweeper via various connectors 46 and brackets. Hood connectors 46 include brackets configured to receive connecting members from the sweeper, such as connecting arms and a connecting piston 96. The connecting arms are connected to the hood via connectors 46 at hood 18 as shown. The connecting arms allow the hood 18 to rotate relative to the sweeper while still supporting the hood 18.

The connecting arms are also pinned to the sweeper, but are shaped such that forces that lift and drop the hood 18 are appropriately transmitted through the connecting arms. The connecting arms are made to deform when forces are exerted on hood 18 that attempt to rotate the hood 18 over the pavement. The connecting arms, then, are the portion of the sweeper that is most susceptible to damage due to impacts from debris to the hood 18. This allows a simple connecting arm, instead of the hood portions, to be replaced upon the occurrence of damaging impacts.

The hood 18 is also connected to the sweeper through a piston 96. The piston 96 attaches to two pulleys 98 through guide wires 100, and mounting brackets 102 attach the pulleys to the sweeper. The guide wires 100 are attached to the hood 18 through a pair of eye bolts 110. The piston 96 is configured to quickly lift the hood off the pavement with controls for the piston 96 located within the cab of the sweeper so that the operator may lift and lower the hood from within the cab while operating the sweeper. By popping the hood up, the operator may be able to clear larger, lighter debris that are unable to be swept under the front flap 36 of the hood 18. Lighter, larger debris are more difficult to ingest under hood 18 than other debris because larger debris require more force to be pushed under the hood 18. When debris cannot transit under the hood, the debris builds up in front of the hood 18 and limits the effectiveness of the sweeper. When the operator engages the piston, the piston length shortens and the hood 18 is raised. The operator may thereby keep the hood 18 raised as the operator drives over the debris so that the debris is swept under the hood 18. When the hood 18 is simply kicked up, then the debris is funneled between the interior flap and back flap of the hood 18 and may be removed from the paved surface into the hopper. This saves time and labor where an operator previously would be required to push debris from the front of the hood 18 after stopping the sweeper and laboring in front of the hood 18 to remove the debris.

While the piston 96 has been attached to the hood 18 through guide wires, it may be possible to directly couple the piston 96 to the hood 18. Moreover, it may be possible to provide the same effect through other means besides a piston. For example, a four bar linkage, a motor, or a screw drive may raise the hood 18 in order to clear debris from the front of the hood 18.

As will be apparent to one skilled in the art, various modifications can be made within the scope of the aforesaid description. Such modifications being within the ability of one skilled in the art form a part of the present invention and are embraced by the claims below. 

1-20. (canceled)
 21. A hood for a mechanized sweeper, comprising: a. a left portion having an upper surface extending in a first direction; b. a right portion having an upper surface extending in said first direction; c. a central mating surface configured to attach to said left portion and said right portion; and d. connectors configured to attach said left portion and said right portion to said central mating surface.
 22. The hood of claim 1, further comprising a front flap extending downward from underneath a front portion of said left and right portions, said front flap having an arcuate shape.
 23. The hood of claim 2, further comprising a rear flap extending perpendicularly downward from a rear portion of said left and right portions.
 24. The hood of claim 3, wherein said rear flap further comprises a cartridge including a resilient member.
 25. The hood of claim 4, further comprising a plurality of adjustable connectors configured to adjustably attach said resilient member of said rear flap to said hood.
 26. The hood of claim 5, wherein said plurality of adjustable connectors comprise fasteners adjustably received in said hood and connected to said cartridge such that adjustment of said connectors lowers said rear cartridge relative to said hood.
 27. The hood of claim 3, further comprising a middle flap, said middle flap position between said front and rear flaps and including a vertical resilient portion.
 28. The hood of claim 5, wherein said plurality of adjustable connectors are further configured to adjustably attach said resilient member to said hood.
 29. The hood of claim 8, wherein said plurality of adjustable connectors are bolts rotatably received in said hood.
 30. The hood of claim 9, wherein said bolts are configured to compress an upper edge of said resilient portion between a portion of said bolts and said hood.
 31. The hood of claim 7, further comprising two end skirts configured to extend perpendicularly downward from said hood at the outer sides of said hood.
 32. The hood of claim 11, wherein said hood further includes a securing rod for compressing a portion of said front flap against said hood.
 33. The hood of claim 12, wherein said securing rod may be moved from a first position to a second position such that the height of said front flap may be adjusted relative to said hood.
 34. The hood of claim 13, wherein said rod is substantially co-extensive with the width of said hood.
 35. The hood of claim 14, wherein said front flap includes an upper edge, said upper edge affixed to said left and right portions.
 36. A hood for a mechanized sweeper, comprising: a. a left portion having an upper surface; b. a right portion having an upper surface, said left and right portions coplanar with respect to each other; c. means for mating said left portion and right portions together; d. a front flap configured to extend arcuately downward and forward from said hood; e. a rear flap configured to extend perpendicularly downward from said left and right portions; f. a middle flap interposed between said front and rear flaps; g. end skirts configured to extend perpendicularly downward from said hood at its sides thereof; and, h. said middle flap, said rear flap, and said skirts defining a vacuum plenum underneath said hood.
 37. The hood of claim 16, wherein said front flap comprises a resilient member having an upper edge fixed to said hood at an underneath surface thereof.
 38. The hood of claim 17, wherein said front and middle flaps are co-extensive with one another.
 39. The hood of claim 18, wherein said front and rear flaps are vertically adjustable relative to said left and right portions.
 40. A hood for a mechanized sweeper, comprising: a. left means for defining a left portion of said hood; b. right means coplanar with said left means for defining a right portion of said hood; c. said left and right means joined together at their edges thereof; d. front means depending arcuately downward from said left and right means for defining a front vacuum barrier to said hood; e. rear means depending downward from said left and right for defining a rear vacuum barrier to said hood; f. middle means depending downward from said hood and interposed between said front and rear means for enhancing said front vacuum barrier; g. two lateral means depending downward from said hood at its sides thereof for defining two side vacuum barriers; and, h. said left, right, front, middle, rear, and lateral means defining a vacuum plenum under said hood.
 41. A hood as recited in claim 20, wherein side, front, and rear means are adjustably connected to said left and right means such that said front and rear means may be lowered relative to said left and right means.
 42. A hood as recited in claim 21, wherein said front flap comprises an arcuately shaped resilient member, said resilient member including at least two slots at an upper portion thereof and fixed at its upper edge thereof to said left and right means, said hood further comprising a securing rod connected to said left and right means at an underneath surface thereof and including at least a pair of fastening means having a portion passing through said slots for biasing said rod against said resilient member such that said front flap is pressed against said underneath surface of said right and left portions, and wherein said fastening means may be moved to lower said resilient member relative to said left and right means. 